.. How do I open the exit hatch?

After you fix the light, someone will close the hatch and leave you stuck. Yikes! Click on the panel to the right of the hatch to start the puzzle.

This is a number pyramid. Every number is added to the one next to it to equal the one above it, so this is a matter of arithmetic and a little logic. Read to the end of this hint for the solution.

The first move is to look at this puzzle in three-number groups (one above and two below) and look for groups where you have two of the three numbers.

If the missing number is above, you can add the two below to find out what it is. If the missing number is below, subtract the other low number from the above number.

For example, if you had this situation --

2 -- #p+

-- 5 - 2 = 3, so the missing number is 2. See? Filling in the obvious missing numbers may give you some more groups with just one number missing, so do those too.

Next comes the logic part. You can only use each number one time, so with the lower numbers, you may be able to figure out what numbers will be used, even if you don't know where they go.

As for the top of the pyramid, you know that the highest numbers need to go up there. Try one and see if you can make the rest of the math work out.

If you can't make any headway with it, here's the solution:

Lighthouse Hatch, Amateur

Lighthouse Hatch, Master

Now that you're out of the cold, remember to call Alex to tell her you fixed the lighthouse if you didn't do so already.